The UK's number one single has reached the top spot with lower weekly sales than any other chart-topping single.
Prydz spent three weeks at number one before his return on Sunday
Swedish DJ Eric Prydz sold 23,519 copies of Call On Me last week to return to the top of the chart.
It was the lowest-selling number one since records began in 1969, compiler The Official UK Charts Company said, as music downloading becomes more popular.
In 1997 Elton John's Candle In The Wind topped the chart with highest weekly sales of more than three million.
In 2002, the finalists of ITV talent show Pop Idol, Will Young and Gareth Gates, both had million-selling singles.
Prydz, whose single samples Steve Winwood's 1982 hit Valerie and was accompanied by a suggestive "aerobics class" video, originally reached number one last month.
After spending three weeks at the top, it was displaced by Robbie Williams' Radio for one week, before returning on Sunday.
The decline in the singles market has slowed this year, dropping 10% in 2004 so far compared with a 30% fall in 2003, said Official UK Charts Company chart operations manager Paul Clifford.
Meanwhile, download sales have taken off, and are estimated to stand at 150,000 per week.
Legal digital music services are seen as crucial to the music industry, aiming to convert file-sharers into customers.
"From nothing, we had quite a strong downloads market," Mr Clifford said.
"People are potentially replacing single purchasing with downloads."
The company has produced its own download chart since September.
"Next year, we are looking at ways of integrating the download chart into the singles chart," Clifford said.